The invention relates to footwear, and more particularly to an insole for a shoe or other item of footwear, containing a moldable, flowable material for conforming to the bottom of the foot of the wearer for greater comfort.
An article of footwear incorporating an insole member having flexible, moldable material for conforming to the user's foot is disclosed in Jackson U.S. Pat. No. 3,968,577. That patent discloses the use of formable, nonsetting silicone material in an enclosure or "casting unit" of the footwear, injected therein either at the time the footwear is purchased, or incorporated in the footwear during manufacture.
While the system of the Jackson patent did function effectively to form an impression of the foot and conform to the contours of the foot for greater comfort, the structure disclosed therein was not useful or adaptable as a replacement insole for shoes or other items of footwear. Moreover, the patent did not address some particular considerations and problems addressed by the present invention, regarding both replacement insoles and insoles permanently secured in footwear. These considerations include flow of the formable material and maintaining of a required thickness of the material in critical areas where the user's concentrated weight would otherwise tend to force all the moldable material out of the particular area, causing that portion of the foot to bottom out.
Neither the Jackson patent nor any other insole or replacement insole in the prior art was capable of providing the continued comfort and reliable, therapeutic support of the present invention described below.